1. Field of the Invention
The present invention relates generally to climbing devices and more particularly to a non-destructive, ergonomic climbing aid for use in climbing a columnar structure.
2. Discussion of Background Information
Ascending certain columnar structures requires deployment of extraneous climbing devices. For example large trees, utility poles, bridge supports and ski lift poles are tall columnar structures having no hand or foot holds for safe ascension and descent. Hunters often ascend trees and perch in upper branches in wait of prey. These trees often lack low-lying, climbable branches, and hunters therefore deploy portable climbing devices to ascend the trunks. These portable climbing devices range from horizontal posts that pierce the cambium layer of a tree, to metal steps that affix to a tree with an encircling strap or tensioned chain.
Post type devices permanently damage living trees, and this deleterious act is often illegal in publicly protected wooded areas. A typical tree climbing step comprises a pyramidal or conical body formed of sheet metal having a support surface that interfaces directly with a tree to provide a small platform for supporting the ball of a foot. When weighted, the typical step slides down the tree trunk, scraping away layers of bark and potentially piercing the cambium layer, until a strap or cord retaining the step stretches fully and provides sufficient tension force to halt movement of the step. This sliding and scraping not only damages the tree, but potentially causes a climber to lose his balance during ascension and descent.
Additionally, these steps fail to provide any ergonomic advantage to a climber because they directly abut the tree and provide little room for sturdy foot placement at a natural stepping angle. This alignment requires a user to wedge his foot directly against the tree so that the instep rests against the tree and only a small, outside edge of the foot rests on the step, potentially causing a misstep or loss of balance and a catastrophic fall. Furthermore, these step devices often provide only a stepping surface and offer no secure, comfortable handholds for the climber to grasp during ascension and descent.
Additionally, existing metal steps would be unsuitable for climbing smooth columnar structures having no bark and little to no surface topography. For example, utility technicians and civil engineers often must climb utility poles or bridge supports for maintenance and inspection. Existing climbing devices would slide down a sheer columnar structure significantly because of a lack of friction. Furthermore, certain columnar structures, such as bridge support I-beams, present a perfectly planar face, further increasing likelihood of slippage because typical climbing aids comprise curved contact surfaces for interfacing with curved columns. Adapting current tree climbing devices for use with columnar structures having planar surfaces would require at least the inclusion of sufficiently large tension straps to provide enough retention force to establish a sufficient factor of safety during use and would require at most a complete re-facing to match the contour of a planar surface.
A need therefore exists for a portable and ergonomic device for safely and comfortably climbing and descending a columnar structure without inflicting damage.